There are many ways in which products, such as food products, may be chilled or frozen. One example calls for the product to be placed into trays. In many cases, a tray is used to enhance the display of the product in the package. It may also be used to contain a fluid such as water or sauce to be chilled or frozen with the product. The tray is part of the final product packaging. Loading trays is labor intensive and is typically done for premium type products which will demand a higher price to offset the additional cost of production. The trays are then placed onto a rack, then placed into a chiller or freezer, or the trays are placed on a moving belt moving through a chiller or freezer.
Another type of freezing for a product is individual quick-frozen (“IQF”). IQF freezing of products provides products that are frozen, but not stuck together. There are several known ways that IQF product is produced. One process is to simply freeze the products without allowing same to contact each other. This may be done by spacing individual product on a freezer belt or rack so they are not in contact with each other. In most cases, this is not done for smaller products because it requires staff to arrange the product fed into the freezer and is an inefficient use of manpower and space, thus reducing capacity. Accordingly, as the pieces to become frozen become smaller, it becomes increasingly more time consuming and difficult to do. Another process is by placing the products into a tray or compartments, which is constructed to keep the individual pieces separated. This is not as desired a process due to the additional cost, labor and increased package size.
Other methods of producing IQF products include fluidized beds, nitrogen immersion or multi-pass tunnels. All of these allow for product to be randomly placed on a belt for freezing. Movement is created between adjacent pieces of product to prevent sticking, thereby creating IQF, to keep pieces of product moving in relation to one another. For example, in nitrogen immersion, the pieces are not permitted to contact each other when dropped into a nitrogen bath and are thereby frozen at the surface of the bath before they can contact and adhere to one another. Multi-pass tunnels (including flighted tunnels) drop the pieces from one belt to another repeatedly to break the product apart before it is frozen solid. However, none of these methods is suitable for processing product contained in trays, since known methods would scatter the trays and displace the product from the trays.
To efficiently process tray and IQF products, different types of equipment are employed which are suitable for one, but not both, freezing processes. In many cases, companies make both IQF and tray types of products and attempt to have both processed with the same equipment. Attempts to achieve this are done by removing or bypassing the IQF portion of the freezing line when tray product freezing is desired. This typically requires relocation of equipment and results in a reduction in production capacity due to the removal of part of the process line.